Esteemed Reflectees:
Don't see much commentary on the L-4B, but mine just cratered. Was
in standby when a crack and long fizzle sound came out of the RF section.
The grid resistor opened up, and the meter needle pinned to the left
(minimum) direction.
I happened to be looking right at the RF section when this happened,
and saw no arc or tube glow. Anybody know if this is a common failure mode?
Since the tubes were biased off at the time, parasitics don't seem likely,
and I ohmed the tubes and see no shorts.
I had a diode stack go out on this unit once, but never had a RF
section pronlem in the 12 years I've had this amp.
73 de Jim, KF7E
Jim Henderson
jhenders@zianet.com
jhenders@tdrss.wsc.nasa.gov
kf7e@k5di.nm.usa.noam
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